Method of assembling a machine tool and the like



Jan. 24, 1967 "I'AMAKI TOMITA METHOD OF ASSEMBLING A MACHINE TOOL ANDTHE LIKE Filed Deo 3 Sheets-Sheet 1 INVENTOR.

TOM/ 774,

Jan. 24, 1967 TAMAKI TOMITA METHOD OF ASSEMBLING A MACHINE TOOL AND THELIKE 3 Sheets-Sheet 2 Filed Dec. 17, 1963 FIG. 8. 22,23 BWMQQ/ZI TAMAKITOMITA Jan. 24, 1967 METHOD OF ASSEMBLING A MACHINE TOOL AND THE LIKE 5Sheets-Sheet 5 Filed Dec. 1'7, 1965 FIG. 9.

11' 9 JBJ INVENTOR.

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United States Patent O 3,299,498 METHOD OF ASSEMBLING A MACHINE TOOL ANDTHE LIKE Tamaki Tomita, Okazaki-shi, Aichi-ken, Japan, assignor toToyota Koki Kabushiki Kaislra, Kariya-shi, Aichiken, Japan Filed Dec.17, 1963, Ser. No. 331,308 Claims priority, application Japan, Sept. 28,1961,

2 Claims. (Cl. 29407) This invention relates to a method of assembling amachine tool and the like.

This application is a continuation-in-part of my copending application,Serial No. 207,251, filed July 3, 1962, now abandoned.

In the assembling of a machine tool and the like which require highprecision, it is the general practice to use a level vial and anadjusting means such as a jack bolt on and against a floor surface sothat the datum level of a bed of a machine tool is adjusted to bepositioned horizontal and, after the adjustment, a head stock or thelike is assembled to the bed. Now when the bed is moved onto anotherfloor for the following station of assembly, it is necessary to make thedatum level of the bed horizontal again due to the fact that thesefloors are not in parallel with each other. An appreciably long periodsuch as several hours is wasted by even a skilled worker when makingsuch level adjustment due to the fact'that a bed is high, unevenlyshaped and not absolutely rigid. Thus, it has been difficult to assemblea machine tool and the like by a conveyor system.

One object of this invention is to provide a method of using a conveyorsystem in the assembling of a machine tool and the like which requirehigh precision, whereby a bed of such a machine tool is conveyed on abase and is very easily positioned horizontal whereby it is possible toassemble such a machine by a conveyor .system.

system in which a base embodying this invention is used;

FIG. 2 is an enlarged fragmentary sectional front view of the conveyorsystem shown in FIG. 1;

v FIG. 3 is a plan view of another base similar to that shown in FIG. 2;FIG. 4 is a further enlarged vertical section showin the relation of asupporting means to a driving meanstherefor;

FIG. 5 is a bottom plan view taken along the line '55 of FIG. 4;

FIG. 6 is a schematic side elevation of two stations in accordance withthe present invention;

FIG. 7 is a cross-sectional view taken on line 77 of FIG. 6;

FIG. 8 is an enlarged plan view of a station;

FIG. 9 is a side view of a further embodiment of the 1 invention; and

FIG. 10 is a sectional view taken on lines 10-10 of FIG. 9.

Referring more particularly to the drawings, the pr eferred embodimentof this invention will now be described; however, this description willbe understood to be illustrative of the invention and not as limiting itto .the particular construction shown and described. A bed '1 of amachine tool is set on a base 2 which is of a suffian assembly systemfor assembling the machine tool in.

cient size and rigidity. There is a pair of conveyor rails 3 fixed on afloor a supporting a plurality of said bases. The base 2 has wheels 4adapted to run on the rails 3, and a bottom wall 2'. The bottom wall 2is provided with three holes for the main supporting means and one holefor the stabilization means of base 2. Each hole is covered by an uppercover 14 and a bottom cover 12. The upper cover 14 is fixed on the uppersurface of the bottom wall 2 and the bottom cover 12 is fixed on thebottom surface thereof. The two covers 12 and 14 are so arranged as toslideably support a leg 5 extending vertically therethrough. The leg 5penetrates upwards and downwards beyond the two covers 14 and 12,respectively, and is keyed to cover 12 for being retained againstrotation. A threaded portion b is formed in the middle of the leg 5. Aworm wheel 6 is threaded centrally so as to engage with the threadedportion b of the leg 5. The worm wheel 6 is arranged between a thrustbearing 13 kept on the bottom surface of the bottom wall 2' and theupper surface of the bottom cover 12 and is rotatable with respect tothem but not displaceable vertically so that the leg 5 may be movedvertically by rotating the worm Wheel 6. Three of the four legs are mainsup porting legs 5 and one is a stabilizing leg 5 for stabilization ofthe base 2. The latter leg 5' is constituted similarly to the mainsupporting leg 5. According to circumstances, there may be provided moresupporting legs 5' for stabilization. The three main supporting legs 5are positioned so as to support the base 2 at three points. One or morestabilizing legs 5' is provided at the position for stabilizing the base2 after the datum level thereof is made horizontal.

A horizontal shaft 11 is borne by the bottom cover 12 and the bottomwall 2' and has a worm 7 meshing with the worm wheel 6. The horizontalshaft 11 is extended to a convenient place on the bottom wall 2 of thebase 2 where other horizontal shafts for other legs are also extended. Abevel gear 8 is fixed to the centralized end of the horizontal shaft 11.Another bevel gear 9 meshing with the bevel gear 8 is fixed on avertical driving shaft 10 which penetrates upwards through the base 2 soas to provide a handle d on the upper end of the driving shaft 10.

In operation, the handle d is rotated so as to rotate the drivingvertical shaft 10 normally, whereby the worm 7 is rotated from thevertical shaft 10 through the bevel gears 9 and 8 and the horizontalshaft 11'. Then the worm wheel 6-meshing with the worm 7 is rotated.Since the worm 'wheel 6 does not move vertically, the leg 5 meshing withthe worm wheel 6 is made to move vertically, or to descend. When thehandle d is rotated reversely, the leg 6 ismade to ascend. Thus, thelegs 5 can be lowered raising the base 2 above the rail 3.

For detecting whether the base 2 is set on the rails 3 or is in thecourse of assembly on the floor a, a limit switch 15 is provided abovethe upper end of the leg 5 within the base 2. It is to be understoodthat such a limit switch may signal the condition of.the base 2electrically.

In accordance with this invention, a bed 1 of a machine tool is set onthe base 2 which is made to run on the rails-3 to successive assemblingstations. At each of the stations, the base 2 is stopped and raised byrotating the handle d. In this way, the bed 1 is leveled through base 2by means of three point support. After the first station assembly hasbeen finished, the base 2 is lowered by rotating each handle d so as toset the base 2 on the rails againand make the base 2 run to the nextassembling stations. Consequently, leveling can be made accurately andsimply,

Modifying this embodiment, the legs 5 may be moved vertically by ahydraulic or an electric means. In accordance with a furthermodification of this invention, it is possible to provide a set ofsupporting means in the floor a for substituting for the legs 5 providedin the base 2. In this case, the wheels 4 or a suitable displacing meansonly may be provided in the base 2. When such a base 2 has arrived at astation, the supporting means provided in the floor a of the station israised so as to raise the base 2 and the limit switches provided on thefloor a may indicate the condition of the base 2.

Referring now to the modification shown in FIGS. 6-8, inclusive, aplurality of bases 16, each being of required size and rigidity, isprovided for a bed 1 of a machine tool to be assembled. There are aplurality of stations, each for a fixing or subassembling operation ofindividual parts of the machine tool. The bases 16 are provided so as tocorrespond to the stations. Each base 16 has four wheels 17 to supportand displace the base 16 on the rails 3 and suitable means for drivingit. It is preferred to provide a suitable connecting means 17 forconnecting the bases 16 with one another.

There are at least three supporting bolts 18 provide-d in the floor awithin any one of the stations. It is necessary to arrange thesupporting points at salient points of a polygon, of which the middlepoint comes almost under the center of gravity of the base 16 carryingthe bed 1, whereby the base 16 is supported at three points. There isalso illustrated a stabilizing bolt 18 which is provided for stabilizinga base 16. It is possible to provide more or less stabilizing bolts asthe case may be, considering the stabilization of the base 16. A casing26 capped by a cover 28 is embedded in the floor a, so as to form achamber, through which the supporting bolt 18 is extended. A worm wheel19 has the supporting bolt 18 therein and a screw b is provided betweenthem being fixedly connected to the bolt 18 and in threaded engagementwith said Worm Wheel. A key 28 is provided for preventing the supportingbolt 18 from rotation, so that the supporting bolt 18 is movedvertically by rotating the worm wheel 19. The upper end of the wormwheel 19 is faced by the cover 28 and the lower end of the worm wheel 19is supported by a thrust bearing 27 provided on the bottom of the casing26. A worm 20 is mounted on a shaft extended horizontally inside thefloor a, and engages with the worm wheel 19 within the chamber. A bevelgear 21 is mounted on the extended end of the shaft 25 which is engagedwith another bevel gear 22 fixedly mounted on the bottom end of avertically arranged driving shaft. The top end 24 of the driving shaft23 is extended upwards so as to be exposed above the floor a, andadapted to engage with a removable handle d. Each of the supportingbolts 18 and the stabilizing bolt 18' is constituted similarly and thedriving shafts 23 are centralized at a place where it is suitable tooperate them while observing level vials mounted on the bed 1. There arelimit switches 15 for bolts 18 and 18' for indicating the motions of thebolts 18 and 18' electrically, respectively.

In the operation of the device, a bed 1 of a machine tool or the like isset on a base 16. Several level vials are set on a top surface of thebed 1. The base 16 is brought to a station. A worker placed at thestation operates the handle d so as to rotate the vertical shafts 23 inone direction, observing the level vials, whereby the base 16 is raisedabove the rails 3. Particularly, he rotates one vertical shaft 23 so asto raise a supporting bolt 18 until the top of the supporting boltarrives at the bottom surface of the base 16 and further raise the samemore, whereby a corresponding corner of the base 16 is raised above therail 3. Next the worker rotates another vertical shaft by the handle dso as to raise another supporting bolt which is arranged near thelongitudinal other end of the base 16, observing a level vial arrangedalong the length of the base 16. Thus, a lateral side of the base 16 israised above the rail 3. Then still another supporting bolt is raisedsimilarly, observing another level vial arranged along the breadth ofthe base 16, whereby the base 16 becomes supported at three pointsprovided by the three supporting bolts, and it is very easy to keep thetop surface of the base 16 horizontal in such a manner as above. Ifnecessary, stabilizing bolts 18 are provided and operated similarly, sothat it becomes possible for the worker to ride on the base 16 to fix orsubassemble a part of the machine tool on the bed 1. It is to be notedthat the stabilizing bolt 18 is not to be operated independently of thesupporting bolts 18. When all bolts are in use, the situation isindicated to a foreman by the operation of the limit switches 15.

When the assembling operation at the station such as fixing orsubassembling of a part of the machine tool is finished, the workeroperates the handle d reversely rotating the handle d in the reversedirection so as to reset the base 16 on the rails 3. This reset isindicated to the foreman by the limit switches 15 so that he may controlthe movement of the bases 16 employed on the track upon confirmationthat all bases are on the tracks 3. Then he may move these bases to thefollowing stages of the assembling operation, respectively.

FIGS. 9 and 10 show another embodiment of this invention, where therails 3a for displacing the bases 2 are secured by a ceiling so as toconnect the assembling stations one after another. As many cranes 30 asthe bases are provided along the rails 3a. That is, there is provided acrane belonging to any one of the stations. In addition, hoists 31 andropes 32 are provided so as to raise, lower, and displace the base 2.Each station for the subassembling or fixing operation is provided withsupporting bolts and stabilizing bolts similarly to the precedingembodiment. After a base 2has been set on the supporting bolts by meansof the crane 30, the bed 1 is leveled similarly to the precedingembodiment. By virtue of the arrangement in accordance with thisembodiment, when the base 2 is provided with rigidity and flatness as abed plate, it is possible to make practically horizontal without anyadjustment of the supporting bolts.

By virtue of this invention, the worker at a station may use merely aspecialized tool for a finely divided single assembling operation. Inaddition, in accordance with this invention, the base is made horizontalwithin a few minutes so that it becomes possible to reduce the totalassembling time down to two-thirds of that in accordance with the priorart.

While particular embodiments of the invention have been illustrated anddescribed, further modifications thereof will readily occur to thoseskilled in the art. It should be understood therefore that the inventionis not limited to the particular arrangements disclosed but that theappended claims are intended to cover all modifications which do notdepart from the true spirit and scope of the invention.

What I claim is:

1. A method of assembling a machine tool and the like which consists inproviding a track and a plurality of wheeled bases adapted to move onsaid track through a series of fixing stations, setting a bed of saidmachine tool on said base, providing at least two level vials on thedatum level of said bed, staying said base at each of said stations,rotating at least three driving shafts provided in the station havingsaid base thereon so as to raise said base above said track whileobserving said level vials so as to make said datum level horizontal,fixing a part of said machine tool on said bed, rotating said drivingshafts reversely, respectively, so as to lower said base down onto saidtrack, and displacing said base to the next station on said track forfixing another part of said machine tool on said bed at said nextstation in the same manner as at the firstnamed station.

2. A method of assembling a machine tool and the like which consists inproviding a track and a plurality of wheeled bases adapted to move alongsaid track through a series of fixing stations, setting a bed of saidmachine tool on said base, providing at least two level vials on thedatum level of said bed, staying said base at each of said stations bylowering said base by a crane provided at the station having said basethereabove on at least three supporting bolts providing within saidstation, making said datum level horizontal by raising and lowering saidsupporting bolts while observing said level vials, fixing a part of saidmachine tool on said bed, raising said base above said supportingbolts'and displacing said base from said station to the next station bysaid crane for fixing another part of said machine, tool on said bed atsaid next station in the same manner as at the first named station.

References Cited by the Examiner UNITED STATES PATENTS 1,417,639 5/1922Sterner 248188.4 1,682,066 8/ 1928 Casey 25486 2,028,999 1/ 1936 Seitz254-86 2,828,578 4/1958 McCabe 248188.4 3,026,607 3/ 1962 McNulty 2940710 3,183,581 5/1965 Lister 29200 JOHN F. CAMPBELL, Primary Examiner.

THOMAS H. EAGER, Examiner.

1. A METHOD OF ASSEMBLING A MACHINE TOOL AND THE LIKE WHICH CONSISTS INPROVIDING A TRACK AND A PLURALITY OF WHEELED BASES ADAPTED TO MOVE ONSAID TRACK THROUGH A SERIES OF FIXING STATIONS, SETTING A BED OF SAIDMACHINE TOOL ON SAID BASE, PROVIDING AT LEAST TWO LEVEL VIALS ON THEDATUM LEVEL OF SAID BED, STAYING SAID BASE AT EACH OF SAID STATIONS,ROTATING AT LEAST THREE DRIVING SHAFTS PROVIDED IN THE STATION HAVINGSAID BASE THEREON SO AS TO RAISE SAID BASE ABOVE SAID TRACK WHILEOBSERVING SAID LEVEL VIALS SO AS TO MAKE SAID DATUM LEVEL HORIZONTAL,FIXING A PART OF SAID MACHINE TOOL ON SAID BED, ROTATING SAID DRIVINGSHAFTS REVERSELY, RESPECTIVELY, SO AS TO LOWER SAID BASE DOWN ONTO SAIDTRACK, AND DISPLACING SAID BASE TO THE NEXT STATION ON SAID TRACK FORFIXING ANOTHER PART OF SAID MACHINE TOOL ON SAID BED AT SAID NEXTSTATION IN THE SAME MANNER AS AT THE FIRST-NAMED STATION.